Current-controlling system.



BEST AVAILABLE C PATBNTED JAN. 3, 1905.

- A. 0 EASTWOOD.

CURRENT OONTROLLINQ SYSTEM.

Arrmoulon FILED we. a. 1904.

WZZncssesF 72126;:207: Q'fiZ/zurlasiwoad 25 715 0250177015 eta-mm grimy concern:

a predetermed'amounti con nectionf with-gu'electric-motor', as Will'un- .vide a motor-controlling-system'with an auto when its load 'is' increased'to a predetermined ance in circuit with the motor.

apparatus for carryin 'outmy'iiivention.

. 1 AM 2 R. 2 S' OQ OF QLEVELAND, cine.

ememgmxitfig part of Letters Patent No. 77e,2e7,' dated January J -..Lppiioatlon mm Lu'gnnt 9,1904. Berial No. 220,138.

Be it known thzitL-Aazmua C; Easrwoo'n, a citizen of'the' UnitedfStates, residing in Cleveland, Ohio, have invented .c'ertain Improvements in Current-Controlling Systems; of which the folldwin'g'is a-specificatiom Qneobjectofi: my-invention is to provide such 1 a" combination'of electrical ap -arms; which in the-presenti'ristanee is employed in der dperating conditions'prevent injury to the motor and 'to the machine 'operatedf'thereby' eventhough-an excessiveioed beanpiied hameless. w A furtherohject of thei'nvention is to promaticaiiyopereting'current-limiting device, so arranged and connected thalt the motor will be placed in'circuifivvith' a protective device extent and will te -hutorhsticelly accelerated to full speed when ."said -loed is decreased by Another 'obje'ct-of' the invention is pro .vide "n electriealde'vice, such as a. motor, with' a hunk of'resistanceand automatically-operating switches}for',shortcireciting. the same, together with a'n -:iu'tometicaily,-, operating s'witkzhffor controlling-the operation of the short-'circuitingswitchesyso arranged that when currentjiowing to the, motor exceeds a predetermined-amount the automatic switch operates to cause the short-ci'rcuitingswitches to open; and thereb; place the bank of resist- These objects .I' attain its hereinaiter'set forth, reference being iled to theaccompanying drawing, in which the figure is a dizigra'mmatic representation of one arrangement of .ln-the figure, A- is-t e-armature of. scornpound wound r'notnr having a' series" field winding Fenda-shdritfield-winding-fi;'

R is-a-hank of startiiig'iresistanee,'aind R is .a bank: of braking resistance, connected, as hereinafter descrihedsoes to be'placedacross the armature+terminals of he motor'ivhen' it, is desired to'bring itto a standstill. I

Bis the inein switch,' to which currentjs'up ply wires nre-eonnectedfland Cris an-over load-circ1iit breaker ofnnzv desired construe-J tion, having'one terminal connected the. Bend its secondterminal connected to one end of'the 'hankfof,

positive pole of the switch resistance R. v i i f BER, R, and R are autoinaticallyoper-. ated switches, eachjhaving one terminal con: nected to a different point of the" bank of resistence R and theirsec'ondflterminals all co'n -W; ne'cted. together and in 'seriesiwith two coils 60 d and (2, also inseries, whdse free te'rn inel. is in turn connected ,to the wire connecting the resistance R and i the circnit-hreaker Coils Mfr, r, and r; respectively',' eoiitroltheop-{ eration of the switches Rto R, 'inclu'sive be: 6.5 I

. i ng connected so as to operatefautoniaticell y in'.

the rm'inrier described and'e'laimed' in m vap- 'plicationfor patent,Serial No. 2l1;210; 'Itniay be stated, however, that one terminalof each coil is connected'to that terminal of its s'witchf 'wh-ich is in direct cominunicationwith the re-;:

sistance-R,'whil e all of the'isecond terrninals, of said-coils are connected to each-other and;

to the negative supply-main tllrougll segments it h and operating lever lzf'of a reversing-. 7 5 switch H. In thecase of switches Rf, R, and B there is interposed in the circuits of their respective coils auxiliary:switchesri41,1and 1", the switch 1" being controlled. bya contact: carried on the blade of the switch Hitheswitch 1 being similarly controlled bye eon-fl tztct on the 'blade'offswitch R, and; so ,on. In thecase of the coil 2-, belonging-t0 thes'witch RJthere is connected in l'seiies' withfit two switches dand d, whose'ppenin'g I1 (1: Lfl,(j s ,8'5- ing are controlled by iluiig'ers pperatin'g'jum j 1 4 der the action otthe coilsdend i 'thet .isto say, when the plunger's'of thez'ssid coils lel re actuated contact-bar g is n ovecl'vout efferi-j; gagement with the contncts o'f its: particular, switch, so as to open-circi it the coil'r'f. In .additioxi to the shove switches there'are, two pairs of's witches E'and;E'fand lihandE/g which together constitute afflve sing-switch for the "motor A, there being inaddi tionf e 5; switch "S, so connected. that whenieloseditshort-circuits the moton srmiitiiretiu'ouglithe bank of resistance-R's :The coilfof thislette'r 1' switch is "permanently;connected direetly f i across the; terminals of said ferma'tureg so that? gee" BESTFAVNLABLE 0 itis excitcd whenever the arim-iture is in rotatioa. Coils e, e, f, and f each have one tcr- Similarly, the second ends'ofcoilsf and f".- ure'connected togethenand to segment It of I aim switch B and the latter, suclrflow taking place from the armutureA-switch F, series field 1?, and to siderableoverload on the motor and'might cause such an increased llo w'ofcurrent as parts shown, .lIOWCVQI' bLY the time the cur Front-has increased to a-predetcr nined point as to move .either one or both of the bars g, with the result that the operating-coil of of the resistance into circuit withthe mothe current'toa safe amount; but.in view of minnl permanently connected to the circuitbreaker C, which will be seen to be connected to-thepositive side of thcsu'pply-line, while the second terminals of coils a and'c' are connected together and to segment I of switch H,

switch H.

",Under operating-conditions, with both the the pircuitbreaker 0 closed a 1d the-lever i of s'witcliH in its central position, there will .be nofiow of current other than through thslrunt-field f of the motori l'fij'no'w theyoperating-lever of switch .H be movedinto the position shown, current will flow ronrthepositive supply inain to coils f in d f, energizing them and causing their respective switch'es'F and F"to close. This. will permit-current to flow to-the armature and, scries fieldof the motorist), as to start positivesupply-main through s'witch B, circult-breaker G, all ofresistanceR, switch F,

the negative supply-main through switch B.

decrease, thus increasing the volmge, applied to the coil r, inasmuch as said coil is excited 'closesvitch R, and with-it switch)". This cuts still' fcrt her speeds up ,the motor, after which switches It; R5, and R are successively closed until finally all of said resistance R is short-circuited. and the motor is operated at full speed. If the motor be so connected a'slto actuate the jaws'of a clam-shell bucket-"such as is em' ployed in the handling of 'ore, coal, &c.-it is found that said jaws often dig into the ore, so as to entrain a greater quantity thereof than the bucket will hold. This un-- de'. operating conditions would throw a coninjure said.motor or strain would seriously -With the arrangement of the machinery;

either one or both of the plungers have been drawn into their respective coils (I and (1', so

*switch'1" is opn-circuited. Said latter switch therefore irpmediatelyopens and by opening the first auxiliary switch '1' causes switches- R, R, audit to also open,- thus throwingah tor. This resistance immediately cuts down safely operate, and inasmuch .theheevy load upon' the' motorthe armature BEST AVAILABLE co wiil bcistallod, so as to beincarmble ot' revolving. 11 now the bucket be raised so as to permit part of the (we or road to fall from the jnws', it will be possible for themotor to again as the bars of switches 1 and d" have immediately closed said switches as soon as the current .fiowing.

to the motor has been reduced by the cutting in of resistance R the arnmture will speed up,

and if the loud be within safe limits the.

switches BF, R, R, and R, will again succes sively short-circuit the various portions of resistance It, so as to bring the motor a second time up to full speed. If theoper ttinghandle If-ot the switch H'he moved sc as to engage the segments/t, /i, and it", there. will be an interval during which it contact with segments 71/. During this time tho-coil s ot-switch S,-which, as before noted, is constantl y'enei'fgiz'ed from the immature of the motor, causes said switch to close-,- thus shortcircuitingsaid armature through resistance R and'specdily bringing it to a standstill. Even though switches E and '15. have their coils e and e'je-xcited from segment 727, these switches cannot close,'since, as described in a. previous application for patent, the, are provided with locking-barse and 1;, of which the first prevents switch E being 'elosedwhcn switch F is closed, and the second prevents either switch E or F being closed while switch S is closed, and viccverszn As soon', therefore, as the armature A has come to rest coil 8 is no longer energized and switch S automatically opens, thereby permitting coil 0' of switchE' to closc said latter'switch, which, since switch E is already closed, permits the above-described cycleof operations to a-gziin take place,

thoughwitli the direction of rotation of the armature reverscc. From the above it will be seen that by my invention I automatically cut down the curan electromagnetic switch'for'controlling the introduction of said current-limiting' means into circuit with said device, a second. clec-, tromagnetic switch connected to short-circuit the current-limiting means, a throttle-switch in circuit with the actuuting-coil of the first switch, and means'in circuit with the electrically-operated device and the second switch foractuating said throttle-switch, substantially as described.

2. A system including a motor, current limiting means therefor including automatic switches having a windingcr windings connected so'that their operation depends on the current-flowthrough the said limiting means,

only.

with mechanisnifor cutting said 'r'neans into circuit with-the motor-when the current-flow reachesa predetermined :inaximum ma-sue.-

sequently cutting-said n'i'eans out of circuit when the current has fallenbelow maxi-' mum, substantially-asdescribed. 1 a

'. -3, Asystem including a motor, abody of resistance, an electromagnetic switch or switches for controlling the .introductionof said re sistance into circuit, a switch in circuit with the coil or coils of the said, electromagnetic switch or switches andmeans actuated by abnormal flow of current to the motor for operating said switch to cause the electromagnetic switch or switches to cut= the resistance into circuit with said-motor, snbstantially as de- ;scribed.- a 'A'system including-a motor, a'body of resistance, a plurality of] automatic switches having theirwindings connected so that their operation depends on the current-flow through said resistance, and means actuated by an abnormal 'flow of currentto themotor-for causing said switches to place the resistance in c'ircuit with said scribedL J Q .5. Acurrent controllingsystemincluding amotor, a body of resistance, aseries of switches series,-with mechanism operated bythe cur for governing the introdnction of said resist ance into circuit, a throttleswitch for governing the opefation of the switches of said rent flowing to the motor for causingjoperation of, said throttle-switch, said throttle' switch and the series of switches being connected to automatically control the currentflow to the motor after the resistance hasbeen cut out, substantially as described. l

6. A ciirrent controlling system i ncludinga' motor, means governing the current-flow thereto, athrottle-switch connected to control the operation of said means after the mtitor has been accelerated, and means in circuitwith the motor for controlling the operation of said throttle-switch,substantially as de} scribed.

-7. Acu rren t-controlling'system including a motor, means-for governing the currentrfiow thereto; a"throttle-switch connected to control said means after the motorhas been accelerated, a winding in circuit with said motor, and mechanism actuated by said winding for.

causing operation of the throttleswitch, su bstantially as described.

8. A current-controlling'syslem including a motor, means for governing the current-flow there'to including a series of electrically-actw ated switches',"-a throttle-switch connected to control said switcheaawinding inci'rcuit' with the motor, and mechanism actuated by said windingfor causingto'peration oflthethrottleswitch, the connections of said apparatus being such that (happening of tbeithrottleswitch causes the opening of said; series of switches, substantially as'described.

motor. substantially as de-'.

. BESTAVAILABLE CC 9. The combination ofan electric motor, a

body ofg-starting resistance, rneansd'ozianto; mati'cally ,utilizingsaid body of ;r esistance in case of digerload for limiting thecurrent flow:

ingto the m'otoi1apdr'neansior aiitoina'tically cutting-out'said resistance to accelerate .said motor after such overload has been removed,

whereby the, operatio u of the auxiliaryswitch is made-to cause openmgof the other switches,

and means, actuated bythe'current passing through'theimotor, for operating said auxiliary switch; substantially as described. v

12. Tl1e combination"of a motor, a bank of resistance-automatic switches for controlling the amount of said resistance incircuit, auxiliaryswitche in circuitwitli the coils of car: tain of the automatic switches and placed to be operated by othersoi said switches, oneof said auxiliary switches being connected to I control all the others, withmeans including a a device connected to be actuated by abnormal current-flow through the motor, forcausing the operation of" the controlling one of the automaticswitches, substantially as described.

' 13. The combination of aseries of automatic switches, a bank'of resistance and a motorco'n-i nected thereto, auxiliary switches in circuit with .the windings of certain of the switches, one of said auxiliary switches being connected to control the operation-of the remaindena winding 1n series-with the motor-armature and means actuated by said winding for cans-- XIO ing operation of controlling auxiliary switch,

substantially as described.

' l4, Thecombination of aseries of automatic. switches, abank of resistance and am'otor connected thereto, auxiliary switches in circuit with the windings of certain of the switches, oneof said auxiliary switches being secon-- nected that its opening causes the openingoi said automatic switches, 'a winding in series with the motor-armature, means for normally maintaining, theico ntrollingauiriliary switch, in a closed condition and an armature, actu e s id 1 .s a Pl c to Qpens auxiliary switch under, predetermined condi .1 2'5 .tions olicurrent-flow, .-substantially as -de- :15.- Asystcm including ,amoto'r, a bank of, resistance, a's'eries ofantomatic switches for controlling-the, introduction of said resistance 

